№ 10103. Типовая задача

from ipaddress import ip_network, ip_address

ip_net = ip_address('244.0.0.0')
ip_host = ip_address('244.55.229.28')

prefixlen = []

for mask in range(1, 32):
    net = ip_network(f'{ip_host}/{mask}', False)
    
    restricted = [net.broadcast_address, net.network_address]
    
    if (ip_host not in restricted and net.network_address == ip_net):
            prefixlen.append(net.prefixlen)

print(32 - min(prefixlen))